Cigarette packs with a lid that is attached by a hinge to one panel of the packet are known. It is a recognised problem for such cigarette packs that they have a tendency not to stay properly closed after the initial opening of the pack. This problem is sometimes referred to as “yawning” or “smiling”. Furthermore, if the pack is held upside down when closed, the lid may open under the weight of the cigarettes inside and hence the cigarettes may fall out of the packet.
The following patent applications provide examples of hinge-lid packets that include a mechanism to counter such yawning: PCT patent application WO 2004/028926, PCT patent application WO 03/039998, U.S. Pat. No. 5,938,018, European patent EP 0894737 and U.S. Pat. No. 5,904,244. Many such existing packs include one or more protruding tabs (“ears”) on the inner frame of the pack. These protrusions engage with the inside wall of the lid (or with a slot on the inside wall) to increase resistance to opening the lid.
It is desirable to provide a hinge-lid pack with improved resistance to opening the lid in order to allow the pack to be closed more securely. It is further desirable to provide a pack which provides an indication to a consumer that the pack is properly closed. It is still further desirable to provide a pack which provides an indication to the consumer when the pack is being opened or closed.